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Subject: Re: [PATCH] driver/mtd:IFC NAND:Initialise internal SRAM before any
 write
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From: Kumar Gala <galak@kernel.crashing.org>
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Date: Thu, 27 Sep 2012 07:33:17 -0500
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To: Prabhakar Kushwaha <prabhakar@freescale.com>
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On Sep 13, 2012, at 3:54 AM, Prabhakar Kushwaha wrote:

> IFC-1.1.0 uses 28nm techenology for SRAM. This tech has known =
limitaion for
> SRAM i.e. "byte select" is not supported. Hence Read Modify Write is
> implemented in IFC for any "system side write" into sram buffer. =
Reading an
> uninitialized memory results in ECC Error from sram wrapper.
>=20
> Hence we must initialize/prefill SRAM buffer by any data before =
writing
> anything in SRAM from system side. To initialize SRAM user can use =
"READID"
> NAND command with read bytes equal to SRAM size. It will be a one time
> activity post boot.
>=20
> Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
> ---
> Based upon git://git.infradead.org/linux-mtd.git branch master
> The compilation of this patch depends upon following patch.
> http://patchwork.ozlabs.org/patch/177893/
> This patch is currently applied on =
git://git.kernel.org/pub/scm/linux/kernel/git/galak/powerpc.git=20
> branch next and status is "Awaiting Upstream"
>=20
>=20
> drivers/mtd/nand/fsl_ifc_nand.c |   56 =
++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 55 insertions(+), 1 deletion(-)

applied to next

- k=